Mine was the same sort of thing.on a beach in Skiathos.finally went for it,and havnt regreted it.been to the swims in Notts .must go more often

If you count public to include other school pupils, mine was when I went to grammar school at 11. After P.E. or sports there were open showers for all. For the first time it was a bit daunting but them from on it seemed perfectly natural thing to do. Suppose that this was my introduction to nudism.

not counting changing rooms or drunken antics [skinny dipping] mine was on beach at Hook of Holland - right there I thought I could live in Holland [language really difficult to pronounce but good beer]

Not including school showers, childhood holidays (where it all began), there was a bit of a lull through the 'teen' years. At the age of about 20, acting on information from a work mate, I visited Telscome Cliffs, wound my way down to the beach and that was that. Any demons all gone. From that time on it was full systems go, not much to stop me. Got 'caught' over the years loads of times.  🙂

I guess we're both quite openminded people and had skinny-dipped and similar amongst friends whilst growing up.   

Our first beach together was whist on holiday in Spain.  I forget which one, but I know it was near a big pink lake.  We were on holiday with friends and whilst the beach was fun, the dunes behind were full of 'meerkats'.  What felt immediately natural though was to strip off and enjoy the sun, breeze and water over our bodies, and the acceptance of other naturists and hence of our own imperfect bodies.

I'd never considered the 'open showers' after PE at school as a factor, and don't think I would.  They weren't particularly pleasant experiences, nor something I looked forward to.

First time naked in public was on my local beach, where nudism is practiced in the more remote locations (seven miles of beach). It was a nervous experience but I enjoyed it in the end.

First time was with an ex-gf whilst island hopping through Greece one summer holiday. We were both students in our late teens in about '83 or '84.
We'd hired a very cheap (and probably very dangerous) motor scooter to go round the island of Thassos and after a couple of hot dusty hours saw a beach below the road which looked lovely. So we stopped and scrambled down the footpath onto the beach. We appeared to be the only people there.
I went to get the swimming gear out of the ruck-sack but my gf just laughed and said why bother as there wasn't anybody around and just stripped out of her shorts and t-shirt and headed for the water. I was a little more reticent, but followed her into the warm sea.
Once I was in the water I never really thought about the lack of clothing.

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Once I was in the water I never really thought about the lack of clothing.

I bet you felt the constriction of Lycra next time you swam in a cozzie.

We did seek out further clothing optional beaches as we travelled around.
Whilst it didn't bother my GF, I was more nervous on the busier beaches where there were more people.
But I always loved it once I was in the water.